LSU AgCenter scientists are working to help farmers protect, improve and better understand the soil.

From planting rotational and cover crops to implementing conservation or no-till systems, there are many practices that offer potential benefits to soil health. AgCenter soil scientist Lisa Fultz has begun a new project examining these methods and quantifying their impact.

Fultz is gathering data from several existing research plots in northeast Louisiana. Using study sites that have been in place for years has its advantages.

“When we implement these conservation practices, we don’t always see the benefits right away. Sometimes it takes three to five years,” she said. “We have this opportunity now to go in and look at fields where these practices have been in place for multiple years and quantify these changes. On a lot of these fields, we also have yield data, so we can also see how yield has fluctuated over that time.”

In another project, Fultz is studying the feasibility of planting cover crops using lower seeding rates.

“The current rates that are recommended are not necessarily based on best practices for cover crops. They’re geared toward grain production, especially for grasses,” she said. “What we’ve found for grasses like cereal rye is that we can plant at lower seeding rates and get as much biomass and ground coverage as the recommended rates while saving money.”

Fultz also is studying timing and methods for terminating cover crops. Farmers need to get rid of cover crops before the growing season for their cash crops — but deciding when to terminate can be tricky.

Fultz is hoping to find a balance between maximizing the benefits of cover crops and terminating them early enough to avoid them turning into weeds that persist once other crops are planted.

Xi Zhang, who is based at the AgCenter Red River Research Station near Bossier City, is working to learn more about managing inputs based on local soil conditions. As a soil physicist, Zhang is studying spatial variability of soil properties. His goal is to learn more about the distribution of different soils in farmland and how those varying textures can affect the movement of water and nutrients.

“In Louisiana, substantial spatial variability of soil properties and thus crop yield has long been recognized by soil scientists as well as farmers,” Zhang said. “For example, the soil type can vary between sandy and silty or heavy clays within the same field.”

To meet yield goals, he said, farming practices should be adjusted to accommodate soil variability. That could mean dividing a field into several smaller management zones where inputs such as fertilizer and water are applied according to soil conditions in a specific area. But there is a limited amount of data to help farmers make decisions about this type of site-specific water and nutrient management.

“This research will help farmers in Louisiana manage agricultural resources more efficiently and enhance grain yields,” he said.

Fultz said all of these projects are important for a variety of reasons.

“From an economic standpoint, all of the resources that producers are putting into their field — fertilizers, herbicides, pesticides — are in some way interacting with the soil. Every time you lose soil off your field, you also lose inputs that plants rely on,” she said. “And from an environmental standpoint, we don’t want to see those inputs being lost from the field because they have the potential to end up in local waterways, and that creates problems with excess nutrients and cloudy water, which influences wildlife and other vegetation.” Olivia McClure